Extension roof-ladder



UNITED STATES PATENT OFFICE.

JOHN L. CRAFTS, OF SOMERVILLE, MASSACHUSETTS.

EXTENSION ROOF-LADDER.

SPECIFICA'IION forming part of Letters Patent No. 434,176, dated August 12, 1890. Application filed June 7, 1889. Serial No. 313,462. (No model.)

To all whom it may concern:

Be it known that I, JOHN L. CRAFTS, of Somerville, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Extension Roof-Ladders, of which the following is a specification.

My invention, relating to roof-ladders, has for its object the provision of such improvements as will render devices of this character extensible, afford means for readily lockin one section to another, and also permit of the means whereby the ladder is applied or secured to the ridge-pole or comb of a roof to be folded into and out of position, so as to facilitate the use of the invention as a roof-ladder, and at the same time by providing one end of the bars with spurs to allow of its ready and convenient employment as a common ground-ladder.

My invention consists, first, of an extensible roof-ladder provided on one end with hooks or similar devices, whereby it may be attached to the ridge-pole or the comb of a roof, second, of a roof-ladder provided with hooks adjustable into and out of position; third, of a roof-ladder provided with hooks adjustable into and out of position, and spurs on one end of the side rails 01' bars; fourth, of an extensible roof-ladder provided with improved means for locking one section to or upon another, and, fifth, of combinations of parts, comprising substantial improvements in roof-l-idders, all as is hereinafter more fully set forth and claimed.

Reference is to be had to the accompanying drawings and the letters of reference marked thereon, forming a part of this specification, said letters designating the same parts or features, as the case may be, wherever they occur.

In the drawings, Figure 1 is a perspective view of a forrnof my improved roof-ladder complete. Fig. 2 isa front view of the upper portion thereof. Fig. is a longitudinal sectional side view of the same. Fig. 4 is a sectional detail on the line 4 4 of Fig.2. Fig. 5 is a sectional view on the line 5 5 of Fig. 3. Fig. 6 is a detail sectional view taken on the line 6 6 of Fig. 2.

In carrying outmy invention I construct the ladder of as many sections as may be de: sired, (two being shown in the presentfim st-ance,) adapting one section to slide upon the other in any suitable way, providing one of such sliding sections witlra latch consist: ing of a base-plate a, constructed to be secured by means of screws, belts, or otherwise to the inner face of a side rail or bar I) of one of the sections, said base-plate being provided with ears 0, in which is pivoted or upon which is hinged a latch (Z, having a notch 6 formed therein,-or otherwise suitably constructed to engage a round of the ladder when turned, as it were, inward or at right angles with the rounds, and to be disengaged from the rounds when turned outward, or in a position parallel with the rounds.

To hold the latch in or out of engagement withthe rounds, I may square its heel at its hinged or pivotal point, as at f, and attach a spring 9 to the base-plate to operate as a jackknife-spring against said square heel, in a well-known way, and all as is clearly shown in Fig. 4, so that said latch may be folded outward to permit of the section to which it is attached to he slid or moved upon another section to properly extend or contract the ladder, and then to be folded or snapped inward over a round of the other section, and so look the two sections together, as before explained.

The upper ends of the side rails or bars I) of my improved ladder are each provided with a hook i, constructed to catch over the ridge-pole or comb ofthe roof of a building, the shank of which hook is adapted to turn in bearings consisting of earsj on the ends of a plate k, secured to the inner face of the side rail. A spring Zis coiled about the shanks of the hooks between the ears], one end of.

said spring being secured to said shank and the other to the ears j, plate 7a, or it may be,

the rail b, and serving to exert stresson the hook with a tendency of turning the latter outward, the shanks of the hooks being adapted to be moved longitudinally as well as axially against the tension of the spring.

n designates clips to the side bars b of one section, and so arranged that the angular part 0 shall engagcggrooves 1), formed in the side bars of the other section, whereby the two sections may be kept from buckling or folding up. The hooks are arranged between the upper two rounds, and so that their free ends may be moved against the spring above or below the upper round, so that when it is desired to have the hooks in operative position they may be moved downward or longitudinally against the springl until they escape the upper round, when the stress of said spring wiliturn them outward, as shown in Fig. 3, in which position they will be held by the spring and may be engaged with the ridge-pole or comb of the roof of a building, and when it is desired to have the hooks in inoperative position they may be moved downward longitudinally and axially inward against the tension of the spring Z until their free ends pass the upper round, when the said spring will force them upward and the said round will hold them in inopcrative position and out of the way, as shown in Figs. 1 and By making the hooks adjustable, as de scribed, I am enabled to greatly facilitate the work of placing the ladders upon and taking them oil trucks or other means of transportation.

\Vith the hooks adjusted in inoperative position the ladder may be used as a common ground or ascension ladder without interference from the hooks, and to facilitate this use I provide one end of the side rails with spurs m, which spurs may form the feet or base of the ladder. The hooks i and spurs m are placed upon the same end or section of the ladder, for the reason that when the invention is used as a roof-ladder it is desirable to have the broader section or portion upward, and when it is employed as a groundladder the reversed position is desirable.

The latch by which one section is locked to another is formed so as to hold the sections from sliding upon each other in either direction, so that when the ladder is employed as a common ground or ascension ladder it may make no difference as to which end is upward or which section is employed as the base or supporting section. Furthermore, it is essential to the practicability of an extension root'-ladder that the sections should be so locked together as that they may beheld from sliding one upon another in either direction, since in moving the ladder up on the roof the sections must be held in one direction, and when the operator climbs upon it the sections must be held locked together in the other direction, as will be readily understood. By the simple means shown and described I have been enabled to overcome a serious obstacle in the way of GOIlSiJlllCtdllg extension roofladders.

It is obvious that changes may be made in the form and arrangement of parts comprising my improvements without departing from the nature or spirit of the invention.

Having thus described the nature of my invention and a form of making and a mannor of using the same, I declare that what I claim is- 1. An extensible roof-ladder provided on one end with hooks 1", pivoted between the two end rounds, constructed and arranged to catch over the ridge-pole or comb of aroof of abuilding, as set forth. v

2. A roof-ladder provided with adjustable hooks 1', pivoted between the two end rounds, constructed to be moved into or out of operative position, as set forth.

A roof-ladder provided with hooks "1", pivoted between the two end rounds, constructed to be adjusted into or out of operative position, and spurs on one end of the side rails of the ladder, as set forth.

4. A roof-ladder provided with hooks constructed to engage the ridge-pole or comb of the roof of a building, said hooks having an axial and endwise or longitudinal movement in bearings connected with the side railsot the ladder, combined with a spring eonstructed and arranged to move said hooks axially and endwise or longitudinally, as set forth.

5. A sectional extensible ladder having one section provided with a base-plate a, and a latch (1, provided with a notch c, hinged upon the said base-plate and adapted to be adjusted to engage with or be disengaged from the rounds of the other section, substantially as shown and described.

6. A sectional extensible ladder having one section provided with a base-plate a, a latch (I, provided with a notch e, hinged upon the said base-plateand adapted to beadjusted to engage wit h or be disengaged from the rounds of the other section, and a spring g to hold the latch in either of its adjusted positions, all as set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 53d day of June, A. D. 1889.

JOHN L. GRAF"S.

Witnesses:

ARTHUR W. Guess 1'. av, A. l). HARRISON.

IIO 

